|Year|Actor|Award|Category|Role|Episode|Result|
|---|---|---|---|---|---|---|
|1992|Nancy Cartwright|Primetime Emmy Award|Outstanding Voice-over Performance|Bart Simpson|"Separate Vocations"|Won|
|1992|Dan Castellaneta|Primetime Emmy Award|Outstanding Voice-over Performance|Homer Simpson|"Lisa's Pony"|Won|
|1992|Julie Kavner|Primetime Emmy Award|Outstanding Voice-over Performance|Marge Simpson|"I Married Marge"|Won|
|1992|Jackie Mason|Primetime Emmy Award|Outstanding Voice-over Performance|Rabbi Hyman Krustofski|"Like Father, Like Clown"|Won|
|1992|Yeardley Smith|Primetime Emmy Award|Outstanding Voice-over Performance|Lisa Simpson|"Lisa the Greek"|Won|
|1992|Marcia Wallace|Primetime Emmy Award|Outstanding Voice-over Performance|Edna Krabappel|"Bart the Lover"|Won|
|1993|Dan Castellaneta|Primetime Emmy Award|Outstanding Voice-over Performance|Homer Simpson|"Mr. Plow"|Won|
|1995|Nancy Cartwright|Annie Award|Voice Acting in the Field of Animation|Bart Simpson|"Radio Bart"|Won|
|1997|Maggie Roswell|Annie Award|Best Voice Acting by a Female Performer|Shary Bobbins|"Simpsoncalifragilisticexpiala(Annoyed Grunt)cious"|Nominated|
|1998|Hank Azaria|Primetime Emmy Award|Outstanding Voice-over Performance|Apu Nahasapeemapetilon||Won|
|2001|Hank Azaria|Primetime Emmy Award|Outstanding Voice-over Performance|Various|"Worst Episode Ever"|Won|
|2003|Hank Azaria|Primetime Emmy Award|Outstanding Voice-over Performance|Various|"Moe Baby Blues"|Won|
|2004|Dan Castellaneta|Primetime Emmy Award|Outstanding Voice-over Performance|Various Characters|"Today I am A Clown"|Won|
|2006|Kelsey Grammer|Primetime Emmy Award|Outstanding Voice-over Performance|Sideshow Bob|"The Italian Bob"|Won|
|2007|Julie Kavner|Annie Award|Best Voice Acting in an Animated Feature|Marge Simpson|The Simpsons Movie|Nominated|
|2009|Hank Azaria|Primetime Emmy Award|Outstanding Voice-over Performance|Moe Szyslak|"Eeny Teeny Maya Moe"|Nominated|
|2009|Dan Castellaneta|Primetime Emmy Award|Outstanding Voice-over Performance|Homer Simpson|"Father Knows Worst"|Won|
|2009|Harry Shearer|Primetime Emmy Award|Outstanding Voice-over Performance|Mr. Burns, Smithers, Kent Brockman and Lenny|"The Burns and the Bees"|Nominated|
|2010|Hank Azaria|Primetime Emmy Award|Outstanding Voice-over Performance|Moe Szyslak, Apu Nahasapeemapetilon|"Moe Letter Blues"|Nominated|
|2010|Dan Castellaneta|Primetime Emmy Award|Outstanding Voice-over Performance|Homer Simpson, Grampa Simpson|"Thursday with Abie"|Nominated|
|2011|Dan Castellaneta|Primetime Emmy Award|Outstanding Voice-over Performance|Homer Simpson, Barney Gumble, Krusty, Louie|"Donnie Fatso"|Nominated|

Question: what is the last year in which kelsey grammer won an award for outstanding voice performance for a role on the simpsons?
Answer: 2006